Hand-held packaging for, for example, pourable solid products is commercially available in many styles and sizes, e.g., 0.5-4 ounce boxes, bags, cans, pouches or tubes made of paper, plastic or metal for a range of food items, such as tree nuts, sunflower seeds, pumpkin seeds, caramel corn, peanuts, hard shell chocolates, breath mints, and non-food items, such as paper dips, screws, jewelry beads, etc. Both food and non-food containing hand-held packages are available in a wide variety of sizes and shapes. For example, metal cans made from aluminum, steel and other materials are well-known. Plastic and glass jars, bottles and tubs as well as plastic and paper bags including pouches, envelopes, stick packages, etc. are all ubiquitous in modern commerce. Suitable packaging, e.g., for pourable or flowable articles which comprise a multitude of small solid products ranging from items such as cinnamon candies to BB shot, is designed to contain the product within the package while protecting the product from contamination and deleterious effects from the external environment. Containers may protect their contents from contact or exposure to unwanted materials such as dirt, dust, microbes, insects, air, moisture, sunlight, etc. Also, the materials used in constructing packaging and especially the product contact interior surface layer thereof (e.g., for packaging a product such as a food, nutritional supplement, or drug), should resist migration of chemicals between the product and the package materials. These materials should also resist destruction, e.g., by perforation from the product intended to be packaged.
A variety of closures have been employed or described in the prior art for such packaging, including closures adapted for reclosing, such as zippers, slider zippers, hook and loop type fasteners, and peel reseal closures made. e.g., with pressure sensitive adhesive (PSA). Some closures in the prior art have self-closing features, such as coin purses and certain flexible packaging.
Examples of prior art packaging having zippers, peel reseal closures and other common features include U.S. Pat. No. 5,561,966; U.S. Patent Publication (USPP) No. 2010/0278457 and European Patent Publication No. 1 783 059.
Examples of prior art packaging having openings which are both re-closable and re-openable include U.S. Pat. Nos. 1,798,945; 3,782,601; 3,635,376; 4,907,694; 4,593,408; and 5,037,138; and USPP No. 2005/0035150.
Packages designed for one-handed opening are also known, e.g., U.S. Pat. No. 5,609,419 and USPP No. 2012/0141048.
Packages designed for self-closing devices for flexible pouches are also known, e.g., U.S. Pat. No. 8,485,728; USPP Nos. 2009/0266036, 2009/0269450, 2009/0304875 and 2012/0230613; and France Patent Document No. 1,209,370. The closures in these packages are often circular bands or stays which are arcuate or have convex or concave shapes in cross-section either from top to bottom or along the length of a resilient stay.
As previously noted, a variety of self-closing packages are well known in the art. These packages often employ a pair of spring-like devices variously termed stays, profile members, resilient strips or springs. These spring-like devices often require a pulling force, such as two hands, to grasp opposing package sides to pull apart to open. In some teachings, the spring-like devices utilize indentations, scores, or other thickness variations to provide directionality to resilient deformation forces to facilitate opening and avoid paired deformation in the same direction (termed “same direction bowing”) which defeats opening, (see, e.g., U.S. Pat. No. 3,272,278 (indentations or scores); and U.S. Pat. No. 4,317,478 (bent or creased points)).
Thus, many commercially available food products, e.g., gum, hard shell chocolate candles, mints, nuts, seeds, etc., are packed in packages which are initially opened without any means for re-closing and re-opening or which require the use of two hands to do so or which do not self-close allowing spillage if the package is dropped in an open state.
Disadvantageously, most prior art packaging designed for re-opening and re-closing multiple times (following initial opening) are impossible or very difficult to re-open with a single hand unaided by external mechanical devices. In addition, the problems of (1) inconsistent opening or same direction bowing and (2) ensuring sufficient closure to prevent spilling of contents are areas where improvements are desirable.